Captured image evaluation apparatus, captured image evaluation method, and captured image evaluation program

Abstract

Provided are a captured image evaluation apparatus, a captured image evaluation method, and a captured image evaluation program capable of evaluating a thickness and a density of stacked cultured cells in a short imaging time. The captured image evaluation apparatus includes: an image acquisition section 52 that acquires captured images obtained by imaging a subject under a condition in which a numerical aperture of an objective lens is changed; a thickness estimation section 53 that estimates a thickness of the subject on the basis of a low NA captured image obtained under a condition in which the numerical aperture of the objective lens is relatively small; and a density estimation section 54 that estimates a density of the subject on the basis of a high NA captured image obtained under a condition in which the numerical aperture of the objective lens is relatively large.

What is claimed is: 
     
       1. A captured image evaluation apparatus comprising:
 a processor configured to 
 acquire a plurality of captured images obtained by imaging a subject under conditions in which a numerical aperture (“NA”) of an objective lens is different; 
 acquire a brightness distribution of a low NA captured image among the plurality of captured images; 
 estimate a thickness of the subject on the basis of the brightness distribution of the low NA captured image according to a table in which a brightness of the low NA captured image and the thickness of the subject are associated with each other; 
 acquire a brightness distribution of a high NA captured image obtained under a condition in which the numerical aperture of the objective lens is larger than the numerical aperture of the objective lens of the low NA captured image, among the plurality of captured images, and 
 estimate a density of the subject by calculating a number of peaks per unit area included in the brightness distribution of the high NA captured image; 
 wherein a level of magnification sets a threshold, wherein the thickness of the subject is estimated below the threshold, and wherein the density of the subject is estimated above the threshold. 
 
     
     
       2. The captured image evaluation apparatus according to  claim 1 ,
 wherein the processor is further configured to estimate the density of the subject on the basis of a shape of the brightness distribution. 
 
     
     
       3. The captured image evaluation apparatus according to  claim 1 ,
 wherein the processor is further configured to approximate the brightness distribution using a Gaussian function to calculate the peak. 
 
     
     
       4. The captured image evaluation apparatus according to  claim 1 ,
 wherein the high NA captured image is a captured image obtained at a higher magnification than the low NA captured image. 
 
     
     
       5. The captured image evaluation apparatus according to  claim 2 ,
 wherein the high NA captured image is a captured image obtained at a higher magnification than the low NA captured image. 
 
     
     
       6. The captured image evaluation apparatus according to  claim 1 ,
 wherein the high NA captured image is a captured image obtained by illumination light of a shorter wavelength than the low NA captured image. 
 
     
     
       7. The captured image evaluation apparatus according to  claim 2 ,
 wherein the high NA captured image is a captured image obtained by illumination light of a shorter wavelength than the low NA captured image. 
 
     
     
       8. The captured image evaluation apparatus according to  claim 1 ,
 wherein the high NA captured image is a captured image obtained using an aperture stop having a larger aperture than the low NA captured image. 
 
     
     
       9. The captured image evaluation apparatus according to  claim 1 ,
 wherein the processor is further configured to output the estimated thickness of the subject and the estimated density of the subject. 
 
     
     
       10. A captured image evaluation method comprising:
 acquiring a plurality of captured images obtained by imaging a subject under conditions in which a numerical aperture (“NA”) of an objective lens is different; 
 acquiring a brightness distribution of a low NA captured image among the plurality of captured images; 
 estimating a thickness of the subject on the basis of the brightness distribution of the low NA captured image according to a table in which a brightness of the low NA captured image and the thickness of the subject are associated with each other; 
 acquiring a brightness distribution of a high NA captured image obtained under a condition in which the numerical aperture of the objective lens is larger than the numerical aperture of the objective lens of the low NA captured image, among the plurality of captured images, and 
 estimating a density of the subject by calculating a number of peaks per unit area included in the brightness distribution of the high NA captured image; 
 wherein a level of magnification sets a threshold, wherein the thickness of the subject is estimated below the threshold, and wherein the density of the subject is estimated above the threshold. 
 
     
     
       11. A non-transitory computer recording medium storing a captured image evaluation program that causes a computer to perform a method of, the method comprising:
 acquiring a plurality of captured images obtained by imaging a subject under conditions in which a numerical aperture (“NA”) of an objective lens is different; 
 acquiring a brightness distribution of a low NA captured image among the plurality of captured images; 
 estimating a thickness of the subject on the basis of the brightness distribution of the low NA captured image according to a table in which a brightness of the low NA captured image and the thickness of the subject are associated with each other; 
 acquiring a brightness distribution of a high NA captured image obtained under a condition in which the numerical aperture of the objective lens is larger than the numerical aperture of the objective lens of the low NA captured image, among the plurality of captured images; and 
 estimating a density of the subject by calculating a number of peaks per unit area included in the brightness distribution of the high NA captured image; 
 wherein a level of magnification sets a threshold, wherein the thickness of the subject is estimated below the threshold, and wherein the density of the subject is estimated above the threshold.